Implementation of two-way wireless communication in 2.4 GHz ISM Band using RF Transceiver CC2500 and MSP430(Microcontroller)
CC2500 (Download datasheet) is a low-cost RF Transceiver now available in the market, It cost around ₹350 for the single module for me in India. It is manufactured by Texas Instruments. you can also buy fully fledged evaluation module(a pair of CC2500 evaluation boards) directly from Texas Instruments, But it is little costly for simple projects and tests, where no professional evaluation is required. It is capable of sending small packets of data ( Like temperature value, Humidity etc) and long packets of data in the continuous format. CC2500 has two dedicated FIFO each for Transmit buffer and Receive buffer.CC2500 can be directly interfaced to any microcontrollers in the market (3.3V and 5V Logic). Just have tested it on AVR, Arduino and MSP430(G2553) works perfectly with no level conversion. It is recommended to use level converter or resistors while connecting with 5V microcontrollers like Arduino. But it does not work for me while I put 1K resistor in series with SPI pins. Here in this project, I am just showing the simple demo and working of the CC2500 with MSP430G2553.
MSP430 is an ultra low power microcontroller by Texas instruments.(Download full tutorial) Its main advantage is the ultra low power feature. It has mainly 4 low power modes for different applications and usability. MSP430 is popular among the wearable and portable battery operated devices. MSP is the family name and it has two classes MSP430 for 16 Bit and MSP432 for 32-Bit. MSP430 have different series like F (Flash), FR (Ferromagnetic Memory) etc.. for more details please visit the TI MSP Landing page
FEATURES • Low Supply-Voltage Range: 1.8 V to 3.6 V • Ultra-Low Power Consumption – Active Mode: 230 μA at 1 MHz, 2.2 V – Standby Mode: 0.5 μA – Off Mode (RAM Retention): 0.1 μA • Five Power-Saving Modes • Ultra-Fast Wake-Up From Standby Mode in Less Than 1 μs • 16-Bit RISC Architecture, 62.5-ns Instruction Cycle Time • Basic Clock Module Configurations – Internal Frequencies up to 16 MHz With Four Calibrated Frequency – Internal Very-Low-Power Low-Frequency (LF) Oscillator – 32-kHz Crystal – External Digital Clock Source • Two 16-Bit Timer_A With Three Capture/Compare Registers • Universal Serial Communication Interface (USCI) – Enhanced UART Supporting Auto Baudrate Detection (LIN) – IrDA Encoder and Decoder – Synchronous SPI – I2C
This is a simple program for implementing wireless communication, RSSI calculation using cc2500 rf module from texas instruments. In this project, I am measuring accelerometer data using msp430g2553 and send to another MSP430 controller wirelessly with the help of cc2500. Here I am using ADXL335 as an accelerometer, 16 x 2 LCD module. I think this will be a good example for starting projects in wireless electronics. The RSSI calculation is done In the RX section(by directly reading a register, look datasheet for more details) accelerometer makes use of ADC I am sending the accelerometer data + MSP430 internal temperature + a continuously incrementing variable in a transmitter. and the same is receiving on the other end. The code is completely working